How To
http://elinux.org/Leapster_Explorer:_UART_Boot

This patch is for Emerald Boot version 2.2.2 it contains compile time options
for booting over UART through micromon (MICRO=1). Also for running the bootloader
from NAND (NAND=1), and on a Didj (DIDJ=1). With no options it compiles for NOR
as per usual. MICRO enables NAND with out bootstrapping. DIDJ enables NAND with
the framebuffer memory very low to make room for Surgeon USB Booting. DIDJ and
MICRO can be combined. This will also compile Madrid-Boot for LeapPad although
these options are untested with that version.

Before using copy host_tools/ and packages/ into the source directory.

Example Usage:
source ../crosscompile_env_vars
cd ../emerald-boot/
DIDJ=1 ./install.sh
